Circuit for adjusting the sensitivity of a sensor using a digita

Details Circuit for adjusting the sensitivity of a sensor using a digita Circuit for adjusting the sensitivity of a sensor using a digita

1992-10-19

1993-09-28

Westin, Edward P.

Radiant energy

Photocells; circuits and apparatus

Photocell controls its own optical systems

307311, G01J 132

Patent

active

052488799

ABSTRACT:
A circuit and method for adjusting the sensitivity of a sensor like a phototransistor which is coupled to an Infrared Emitting Diode (IRED). A controller places input data on a counter to vary the duty cycle of the counter and a low pass filter is used to obtain a DC voltage which varies linearly according to the input data placed on the counter. An amplifier uses the DC voltage to control the current passing through the IRED. The controller changes the input data until the output from the phototransistor reaches a predetermined level. A switchable load is added or switched into the circuit to obtain an additional range of DC voltages to be applied to the IRED when the phototransistor is one which does not generate a high output.

REFERENCES:
patent: 4580044 (1986-04-01), Hongo et al.
patent: 4730114 (1988-03-01), Portmann
patent: 4734914 (1988-03-01), Yoshikawa
patent: 4769532 (1988-09-01), Kawakami
patent: 4853934 (1989-08-01), Sakurai
patent: 4922090 (1990-05-01), Turra et al.
patent: 4924790 (1990-05-01), Kondo et al.
patent: 4958069 (1990-09-01), Okamori
patent: 5021676 (1991-06-01), Dragon et al.
patent: 5068540 (1991-11-01), Tsuji
patent: 5105077 (1992-04-01), Asada
patent: 5123024 (1992-06-01), Dowd et al.
patent: 5130524 (1992-07-01), Egawa et al.
patent: 5159184 (1992-10-01), Egawa et al.
patent: 5187374 (1993-02-01), Rogers et al.

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